1. Field of the Invention
This invention relates in general to excavators, and more particularly to soil excavators used for trenching at commercial and industrial sites.
2. Background of the Invention
There has been for some time various water jet/vacuum excavators used to expose underground utilities or piping, as well as for cutting precise trenches for installation of utility lines or piping.
In these prior art excavators, the excavation is achieved through use of a high pressure water jet (>1,200 psi) and the removal of the excavated soil through use of a vacuum system. One example of such excavators is described in U.S. Pat. No. 6,484,422. However, these prior art devices are not capable of operating in all of the various field conditions where the excavation may be desired. In many instances these excavators do not have the mobility necessary to efficiently make the desired shaped trench, or the ability to maneuver in narrow spaces to get to the excavation site, or require too much down time to dispose of the collected excavated soil or are not constructed to efficiently excavate the site. Nor are this prior art devices constructed to deliver other equipment or material to the excavated site without extensive maneuvering or removal of field structures.
Yet another problem is the requirement for extensive equipment operator training. Still further, many of these prior art excavators required multiple personnel to operate the excavation equipment. In many cases the operating personnel have to be positioned in environmental or safety hazardous places that can cause harm or injury to the operating personnel.
Still further, many of these prior art excavators do not have the ability to perform other function that are commonly required in a trenching operation, such as breaking up concrete, picking up and removing obstacles to the excavation process, or cutting material for removal from the excavation site, etc. thus requiring additional equipment and lost down time.
In addition, it is difficult to determine the depth of the excavation during the excavating process, as well as it is difficult for the operator of the excavation equipment to confirm that soil is actually being excavated or determine if the excavated material may be clogging the vacuum hose that removes the material from the site.
Another problem with the use of these prior art excavation devices is damage caused by the trenching tubes striking the coated surfaces of pipes and/or utility lines that are buried underground at the excavation site. Also, a problem is the inability of these prior art excavation devices to be able to detect if explosive gases or environmentally harmful fumes have been released during the excavation operations.
Finally, these prior art excavators are primarily constructed to perform vertical surface trenching, and are not capable of efficiently performing horizontal trenching under pipes or other surface material, such as a concrete slab.